Forage samples were dried (55 C) in a forced air oven for 72 h and
then ground (0.5 mm) in a cyclone mill. Cell wall (CW) used for lignin
extraction was obtained as described previously10with the exception that
filter bags (Ankom Technology Corp., Macedon, NY) were used instead
of glass thimbles (ten filter bags placed in the Soxhlet extraction tube
instead of an individual glass thimble). Also, chloroform:methanol (2:1)
mixture replaced pure chloroform. Concentration of CW was used to
calculate lignin values in the samples.